Refrigerating apparatus



July 15., 1941;

n. o. -wn ngmmmuiua APPARATUS Filed-'llay 14, 1938 INVENTOR ATTORNEYPatented July 15, 1941 Daniel 1). Wile, Utica, N. Y., assignor :6Detroit. Lubrlcator Company, Detroit, Mich, a corporation of MichiganApplication May'14,'1938, Serial No. 207,906

8 Claims. (Cl. 235-92) My invention relates generally to refrigeratingapparatus and moreparticularly to valves for controlling the how ofrefrigerant medium where in the valve is controlled conjointly by thepressure and the temperature of the refrigerant medium. In valves ofthis nature which employ a volatile liquid charged thermostatic elementrelying on vaporization of the liquid for .motive power, some means mustbe provided to prevent chilling of the thermostatic element by the coldrefrigerant medium leaving the valve. Heretofore, this has beenaccomplished by the use of a spacer member'of plastic material such asBakelite, but such members have certain disadvantages such as swellingand cracking due to absorption of moisture, breakage when dropped orstruck severely, and dificulty in maintaining tight joints. It istherefore one object of my invention to provide a valve structure whichwill eliminate these disadvantages. Another object is to provide aspacer member of simple and designates generally a thermostaticexpansion valve having a base or body member 2, arr-upper or powermember 3 and an intermediate or heat insulating member d. The bodymember 2 is hollow having an inlet means or extension 5 and.

an outlet port 6. Within the member 2 there is a lateral projectingportion l extending inward from the means 5. Through the means 5 andportion 1 there is an inlet passageway 8 which opens downward throughthe underface of portion 'I.- Screw threaded, as at 9, into the outerrugged construction which will effectively insulate the power element ofa thermostatic ex- In the accompanying drawing, to be taken as. I

a part of this specification, I have fully and end of passageway 3 thereis a hollow holding member it which receives a valve seat member llhaving an orifice or port l2. A valve needle i3 cooperates with thevalve port E2 to control flow of fluid therethrough, and is mounted onthe lower arm of a U-shaped supporting member H by means of a nut l5.The hollow interior of the base member 2 provides an outlet chamber I6and throughthe body member top wall I! there is an aperture l8. Abellows member I9 overlies the-aperture l8 and is sealed to the top wallI! in fiuidtight relation. The bellows member l9, at'its other end,-issealed in fluid tight relation to a continuous annular 'lip 20 of acup-shapedxmember 2|. The cup-shaped memclearly illustrated myinvention, in which draw- Figure l is a view partly in elevation andpartly in longitudinal central section of a thermostatic expansion valveembodying my invention;

Fig. 21s a detail view in perspective of the intermediate or heatinsulating member of Fig. 1, but with a portion broken away to show theinternal construction;

Fig. 3 is a view in partial central vertical cross-section showing.another formof thermober 2| has an aperture 22 through its base 23'forreceiving a connecting pin 24. The pin 24 has a downward facing uppershoulder. 25 abutting against the base 23 of and within the cup member2|.v The top arm 26 of the U-shaped member vI4 also has an aperturetherethrough for receiving the connecting pin 24. The pin 24 is sestaticexpansion valve embodying my invention;

on the centerline of the valve, Fig. 3, and at right angles to theshowing in Fig. 3.

Referring to the drawing by characters of reference, and specifically toFig. 1, the numeral .l

cured in clamping engagement with arm 26 by a lower flange 21 which maybe formedby peening' over the pin end so that the U-shapedmember I4 istightly held tothe base 23. The pin 24 has a portion.28 which projectsupwardly from the shoulder 25. A bearing pin 29 is screw threaded intothe upwardly projecting pin portion 28 and has, at its opposite end, asocket 30 for receiving a pin or thrust member 3|. The power member 3comprises an inverted cup-shaped casing 132 which houses a bellowsmember 34 and has a lower edge portion 33 of enlarged diameter. Thebellows member 34 has,

at its lower end, and sealed'thereto in fluid tight I I relation, aplate or end member 35. The plate member 35 has a central embossedportion 36 for receiving and guiding a spring 31 located within thebellows member 34. The plate member 35 also has. a central aperturetherethrough for receiving a reduced diameter portion 38 of an abuttingpin member 39 which is held against the plate member 35', as at 40, suchas by peening sealedto a temperature sensitive or feeler bulb 44 to forma closed system. This system is charged with a temperature responsivefluid so that upon increase in temperature of the bulb- 44 the pressurein the system is increased to expand the bellows 34. Screw-threaded, asat 45, into the end p'ortionof the normal diameter at the open end ofthe cap member 3| is an annular plate member 46 having a plurality ofapertures 41 and a central aperture 4| therethrough. Within the aperture4| there isa guide member 48 having an upwardly facing flange portion 50which holds one end of each of a plurality of spring fingers or members5| against the lower face of the plate member 4. The member 49 has aflange portion 52 which overlies member 46 and may be formed, as bypeening, to hold 3- 'theguide member 49 and the plurality of springfingers 5| to the plate member 4. The guide member 49 serves to hold theexternal projecting the normal diameter part of the spring projectsas-19,101 I 68 and has a downwardly projecting embossed.

portion 10 having a central aperture therethrough. A helical tensionspring 12 has the final coil on its upper end of enlarged diameter tofit within the downwardly embossed portion 10, and

downwardly through the central aperture H in the embossed portion 70 andthrough the aperture 62 of the cup-shaped member 6|. At its other endthe final coil of the spring I2 is of reduced diameter and is heldagainst-the upward face of the upwardly projecting pin portion 28 by thebearing pin 29 screw-threaded thereto. The tension spring 12 surroundsthe rod member 3| and holds its opposite ends in the sockets 34 and 42The normal diameter portion I3 of the cup member 6| substantially fitsthe upper inside wall of the cylinder member 55 and is securely fastenedthereto.

the refrigerant cooling coil and intermediate the 'portion 4| of the pin34 in position for reciprocal movement therein in response to the'actionof the bellows member 34. Each of the spring ,members 5| has one facenear its free or other end portion in frictional engagement with the pinmember 39, to prevent excessive transient motion or chattering whichmight otherwise be caused by pressure fluctuation in bellows member IS.The extreme free end of each of the spring fingers 5| is bent away fromthe member 39 in the shape of a hook, as at $3, to form a holding meansfor receiving and holding an endless helical coil spring 54. The spring4 surrounds and holds the spring fingers II in a predeterminedfrictional engagement with the pin member-39. The plate member 44 servesasa stop means to limit downward expansion of bellows 34, as well asholding the guide member 4!. The intermediate member 4 comprises a thinstainlesssteel cylinder member ll which may be made from a rectangular,flat sheet by rolling the fiat sheet and welding the abutting endstogether, as at 56. A ring member 51 having screw threads 58 andthreaded to the body member 2 has a flange portion 58 against which themember 66 abuts. The ring member 81 also has a cylindrical portion 60extending upwardly from the flange portion 58 and substantially fittingthe interior of the member 55 which is secured thereto. The upwardlyprojecting or other end of the cylinder member II has securely fastenedthereto a cup-shaped ring member 4| having a plurality of apertures 42,13 extending through the bottom 84 of the cup member 4|, and whichwardlyfacing cup-shaped member 32 of the power means 3. The threadedconnection of the I 'member 4 with body member 2 and with the powermember 3 is preferably treated with a suitablethread compound tosubstantially preventpassage of moisture therethrough. The cupshapedmember 4| has a shoulder 44' which is formed by the cap portionconnecting the-normal diameter with the enlarged diameter 44. a springholding member ".is supported by the shoulder coil and liquidrefrigerant supply line to control the supply of refrigerant admitted tothe cooling coil. Liquid refrigerant flows from the liquid lineconnected to the inlet means 5 through the orifice I2 into the chamber|6, and flows from the valve through the outlet port 6. The bellowsmember i8 is sensitive to the pressure of the refrigerant within thechamber l6 and the pressure therein tends to close valve needle I3against the seat II and close the orifice I2 to further flow of fluid.The spring fingers 53 which are held against the projecting portion 4|of pin 39 ofl'er friction to movement of the valve and prevent rapidmotion of small magnitude which might cause a chattering noise. Thepower element exerts a force tending to open the valve to flow of fluidand is usually so adjusted that it exerts sumcient force so that whenthe bulb temperature is slightly warmer thanthe temperature oftherefrigerant corresponding to the pressure within the chamber It, thevalve will throttle flow of refrigerant to maintain this predetermineddifferential. As the refrigerant passes from the liquid line through thevalve orifice I! to the chamber I6 and to the lower pressure coils, thepressure is reducedand as a consequence some of the refrigerantvaporizes, bringing the temperature of the remaining liquid to atemperature corresponding to the lower pressure, as determined from thepressure-temperature curves for the refrigerant employed. This of coursechills the body member 2.

The power element system comprising the bellows 36, conduit 43 and bulb44 is charged with a predetermined amount of the same temperaturesensitive fluid as that employed in the refrigerating system, andoperates so that the opening force exerted by the power element isineffective to open the orifice |2"to flow of fluid when the pressurewithin the chamber II is above a pre'- determined pressure. Thepredetermined maximum pressure opening of the valve is accomplished byusing a small fluid charge invthe' power element system. This fluidcharge must will operate to control the fluid pressure within the powerelement system, and controlthe valve operation. To'prevent thisdistillation from happening, the temperature of the bellows 34 must bemaintained warmer than the temperature of the body 2. The flow of heatfrom the power .vented as far as possible, and to prevent this I haveintroduced my stainless steel spacer member which has a low rate of heattransfer and is not subject to changes caused by moisture absorption bythe material, nor is iteasily broken and damaged if struck.

Referring to the construction shown in Fig. 3, the numeral 8i designatesgenerally a thermostatic expansion valve having. a body member 82, apower member 83 and an intermediate or heat insulating member 84. Thebody member 82 is substantially hollow and has an inlet means 85 and anoutlet means 88. Within the body member 82 there is a wall means 81separating the inlet 85 from the outlet." and having an aperture in asubstantially horizontal upper wall 88 in which is screw-threaded a portmeans 89 A plate member 92 having a central aperture therethroughoverlies and issealed in fluid-tight relation with the edge portion ofan aperture 90 through the top wall 9i of the body member 82. Thecentral aperture 93 receives and is substantially closed bya needleprojecting portion 98 to be hereinafter described. Surrounding theportion 93 and having a piston flt relation thereby the incomingrefrigerant, and by any leakage of fluid from the-outlet 01' the valve,through the aperture 93 against the plate 92 to substantially preventfurther flow of fluid through the aperture 93. A bellows member 98overlies the aperture 90 and the plate member 92 and has its lower endsealed in fluid-tight relation between the top wall 8| of the bodymember 82.and the plate member 92. Tothe other end of the bellows member94 is secured, in fluid-tight relation, an annular, outwardly extending,flange portion 95 of a cup member 98 having a portion extending downwardinto the interior of the bellows 94. -A small pressure chamber 91 of avolume substantially less than that bounded by the bellows itseli, isthus formed-within the bellows, having the plate member 92 forming thebottom wall of the chamber 91 and the cup member 98 forming the topwall. The chamber 91 has a connection comprising a means 91-, see Fig.6, extending through and threaded to' the body member 82 and extendingthrough the plate member 82 to provide means for maintaining an externalpressure therein. A valve needle 98 cooperates with the port means 89 tocontrol-flow o1 fluid therethrough. The needle 98 has an upwardlyextending tip portion 98' of reduced diameter which extends through theport means 89 and .with is a cone-shaped member 93' which is urged tolimit expansion 01 the bellows 98'.

aperture 98 or the plate member 92, in a piston fit for reciprocalmovement therein, and substantially seals the aperture 98. The upper endof the tip portion 98- abuts against an end member I00 extending throughand secured to the bottom. of the cup-shaped member 88.

The power member 88 comprises a sealed system. including a bellowsmember (not shown), a

capillary-tube I8I and-a ieeler bulb I82, and is charged with atemperature responsive fluid. Projecting downward from the power member88 hereinafter described. The extreme ends of the v blades are bent awayout of engagement with the member I 01 sothat a smoother engagement ismaintained.

The heat insulating member v8t comprises a stainless steel cylinder I08which may be formed from a flat sheet of metal and the adjacent endsformed as by a butt welded joint I09. A ring member H0 having acylindrical portion III and a flange II 2 is threadedly secured, as atH2, to the body member 82 so that it surrounds the aperture 90 throughthe wall 9| thereof. One end portion of the steel cylinder I08substantially flts the cylindrical portion III and is in abuttingrelation'with the flange H2 and may be secured in this position by anysuitable means. The upper or other end of the member I08 has securedthereto the lip portion 8 of an inverted cupshaped member H8, forscrew-threaded reception in the power member 88. Thebottom'or base II8.of the member I I4 has a large concentric aperture I I1 therethroughanda pluralityoi' smaller aperturesi I8 surrounding the aperture 1.Secured to the base 8- along the periphery oi the aperture H1 andextending within the cylinder I08 is a cylinder member I01 whichcooperates with the spring members I08 to dampen movement thererbetween. The length of the member I01 is so adjusted that it cooperateswith the member 98 Preferably the threaded connections of the member 88with the body. 82 and with the power member 88 are fllled with asuitable thread compound to substantially seal the joints against thepassage of moisture therethrough. I

The operation of the valve shown in Fig. 3 is similar to that of thevalve shown in Fig. 1,

. the main difference being that the pressure within 0 the bellows 98 isnot thepressure oi. the adjacent chamber of the valve body. In thisconstruction a plate member 92 separates the interior of the bellowsfrom the valve body, and the connecting means 91' is added. The usualmethod oi using this valve is to connect the connecting means 91 by aconduit to the outlet'oondiiit from the cooling coil so that thepressure therein at the point where bulb I 02 is located may becommunicated to the interior oi the bellows. By using this method thepressure drop through the coolin coil hasno appreciable effect on theamount of and fastened to the end wall of the bellows (not shown) isathreaded screw I08 having its downward projecting end screw-threaded.as at I04,

.intothe member I88 against which the valve needle extending portion 98"abuts, thereby oper atively connecting the power member 88 to the valveneedle 98. Acup-shaped member I88,

threadedto screw I08, has downward projecting liquid admitted to. thecoil because the pressure and temperature relations by which the valveoperation is governed are taken at one point.

The valve operates to maintain the exit refrigerant vapor at apredetermined-temperature above the temperature corresponding totheoutlet rei'rigerant pressure. 1 v

Fig. '5 shows in detail a portion 01' a modification of the constructionshown in Fig. 3. In this modification. the pressure sensitive bellowsI20 is inverted with respect to the-bellows 98 of Fi 3.

A carrying member I2I having one end secured to the periphery of theaperture 90 of Fi '3 (not shown in Fig.5) carries on the other end andsealed-thereto the upper end of the bellows I20.

nd portions which hold one end or each of a To the lower end oi thebellows is sealed 8. re-

entrant cap member I22 which has aportion I28 extending within the.bellows I28. A stainless III. The side wall portion away from the lipportion I I8 is screw-threaded, as at steel cylinder I24 is sealed to aninverted cupshaped member I25 and screw-threaded, as at I23, to thepower element I2'I carried by a casing I28 in a manner substantially asin Fig. 3. A concentric aperture I23 extends through the bottom wall I30of the member I25, and a plurality of smaller apertures I3I also extendthrough the wall I30 and surround the aperture I29. One end of acylinder I32 is secured to the wall I30 around the periphery of theaperture I29 and has the other end extending within the cup-shapedmember I25 toward the bellows I20. A second cylinder member I33concentric with and. surrounding the member I32 and extending in thesame general direction has one end secured to the wall I30 and has theother end extending within the upper open end of the bellows I20 securedto the carrying member I2I to serve in cooperation with the reentrantcap member I22 as a stop means limiting contraction of the bellows I20.The power element H1 is operatively connected to the cap member I22 bymeans of a rod I34 screw-threaded, as at I35, into a thimble member I38which is secured in an aperture I31 through the reentrant portion I23 ofthe member I 22, and which may be secured by peening, as

p at I39. The thimble member I33 is operably connected to thevalvemember (not shown in this figure) by a rod I60 which abuts themember I36. Secured to the member I36 on the power element side of thecap member I22 is the base of a pair of spring fingers Ill. The free endportions I42. of the fingers Ill frictionally engage the inner walls ofthe cylinder I32 to dampen the movement' of the thimble member I 36,which would otherwise occur with small rapid changes of pressure towhich the bellows I20 is subjected. The extreme free ends I63 oi thefingers MI face inwardly, however, and do not engage any surface. AnutI45 may be screwthreaded to the rod I36 to secure the base of the springfingers Hli to'the thimble member I33.

It will thus be seenthat I have provided a valve which is simple, ruggedand dependable.

What I claim and desire to secure by Letters Patentof the United Statesis: 1. In a thermostatic expansion valve, a body member having anopening through a wall thereof, a pressure responsive member sealingsaid opening, an end member secured and sealed to said body memberaround said opening, a casing member, a thermostatic power elementoperating member positioned in said casing member, thrust meansoperatively connecting said operating member and said responsive member,a connecting member secured and sealed to said casing member and havinga portion projecting toward and concentric with said end member, theadjacent portions of said projectingportion and of said end member beingor substantially equal size, and a thin sheet metal housing member oflow heat conductivity positioned between said adjacent portions, saidhousing member being sealed in fluid-tight relationship at either end tothe respective adjacent portions of said connecting member and of saidend member.

2.. In a thermostatic expansion valve, a. body member having an openingthrough a wall thereof, a pressure responsive member sealing saidopening, an end member secured and sealed to said body member aroundsaidopening, a casing member, a thermostatic power element operatingmember positioned in said casing member, thrust means I operativelyconnecting said operating member and said responsive member, asupporting member having opposite end portions, one end portionconforming to and fitting said end member to provide a sealed joint, theother of said end portions inclu g a cup-like portion having an aperturethrough its end wall for receiving said thrust means,

the side wall of said cup-like portion being secured and sealed to saidcasing member, an intermediate continuous oi! said supporting memberpositioned between end member and said casing member being of metal oflow heat conductivity thereby to maintain a differential of temperaturebetween saidcasing member and said body member.

3. In a thermostatic expansion valve, a body member having an openingthrough a wall thereof, a pressure responsive member sealing saidopening, an'end member secured and sealed to said body member aroundsaid opening, a casing member, a thermostatic power element having anoperating member positioned in said casing member, thrust meansoperatively connecting,

said operating member and said responsive mem: ber, a cup-like membersecured to said casing member and having a central aperture therethroughand having a portion projecting toward and concentric with said endmember, a spring member extending through the aperture in said cup-likemember and having one end supported by said cup-like member, theadjacent portions of said projecting portion and of said end memberbeing of substantially equal size, and a thin sheet metal housing memberof low heat conductivity positioned between said adjacent portions, saidhousing member being sealed in fluidtight relationship at either end tothe respective adjacent portions of said cup-like member and of said endmember.

4. In a thermostatic expansion valve, a body member having an openingthrough a wall thereof, a pressure responsive member sealing saidopening, an end member secured and sealed to said body member aroundsaid opening, a casing member, a thermostatic power element having anoperating member positioned in said casing member, thrust meansoperatively connecting said operating member and said responsive member,a cup-like member secured to said casing member and having a centralaperture therethrough and having a portion projecting toward andconcentric with said end member, a spring member extending through theaperture in said cup-like member and having one end supported by saidcup-like member, the adjacent portions of said projecting portion oisaid end member being of substantially equal size, a thin sheet materialhousing member of stainless steel positioned between said adjacentportions, said housing member being sealed in fluid-tight relationshipat either end to the respective adjacent portions'of said cup-likemember and of said end member, guide means secured to said casing memberand extending toward said body member and operable to guide said thrustmeans, and friction means secured-to said guide means and operable tofrictionally oppose movement of sail thrust means.

5. In a thermostatic expansion valve. a body member having an openingthrough a wall thereof, a pressure responsive member sealing saidopening, an annular ring member secured and sealed to said body memberaround said openlng, an annular flange portion on said ring member, acasing member, a thermostatic power elepart portion projecting said ringmember,

ment having anoperating member positioned in said casing member, thrustmeans operatively connecting said operating member and said responsivemember, a connecting member secured and sealed to said casing member andhaving a toward and concentric with projecting portion and of said ringmember being the adjacent portions of said of substantially equal size,and a thin sheet mate:

rial housing member of stainless steel positioned between said adjacent.portions and having one end abutting said annular flange portion, saidhousing member being sealed in fluid-tight relationship at either end tothe respective.adjacent portions of said ring member and of saidconnecting member, said connecting member bottom portion serving as areenforcing means for said housing member.

6. In a thermostatic expansion valve, a body member having an openingthrough a wall thereof, a pressure responsive member sealing saidopening, an end member secured and sealed to said body member aroundsaid opening, a casing member having a portion of normal dimeter and aportion shoulder on said intersection of said normal diameter portionand said enlarged diameter portion, plate means secured to said shoulderand having an aperture therethrough, a power element .carried by .saidcasing member and' having an operating memof enlarged diameter, a casingmember formed by the ture therethrough secured and sealed to said.

7 being sealed in fluid-tight relationship at either an operating membersaid opening, a casing casing member and having a lip portion projectingtoward and concentric withsaid end member, the adjacentportions of saidlip portion and of said end member being of equal size, a thin sheetmetal housing member positioned between said adjacent portions, -saidhousing member *end to the respective adjacent portions of said her,thrust means extending through the plate means aperture and operativelyconnecting said operating member and said responsive member, springfingers secured to said plate means and irictionally en ing said thrustmeans to dampen movement thereof, a supporting member having oppositeend portions, one end portion conforming to and fitting around said endmember to provide a sealed joint, the other of said end portions beingsealed to said casing member, an intermediate continuous part of saidsupporting member being member and said casing member and being of thinlow heat conductivity metal thereby to maintain a temperaturedifferential between said casing member and said body member.

, blows secured and sealed ment resilient heat insulating metal memberof low end member and of'said cup-like member, a cylinder member securedto said cup-like member concentric with the aperture therethrough andextending toward said body member, and spring fingers secured to saidpressure responsive member 'and frictionally engaging said cylindermember to 'frictionally oppose movement of said responsive member. v

8. In a thermostatic body.

expansion valve, a valve 9. pressure responsive valve operatingelecarried by said body, a thin wailed'tubular heat conductivity capableof withstanding sharp at one end to said body and surrounding saidelement, a cup shaped supporting member having a side wall portionfitting within and secured to the other end of said tubu lar member,said supporting member having a cylindrical screw-threaded side wallportion extending beyond said tubular member, a. thermostatic powerelement having a casing with a screw-threaded flange threadedly engagingsaid positioned between'said end cylindrical portion, and means fortransmitting movement from the movable member of said thermostatic powerelement to said pressure responsive element.

- DANIEL D. WILE.

member sealing said secured and sealed to power element having

